Practicing Success

Target Exam

CUET

Subject

Physics

Chapter

Electrostatic Potential and Capacitance

Question:

Case: Read the passage and answer the following questions

Conductors contain mobile charge carriers. In metallic conductors, these charge carriers are electrons. In a metal, the outer (valence) electrons part away from their atoms and are free to move. These electrons are free within the metal but not free to leave the metal. The free electrons form a kind of ‘gas’; they collide with each other and with the ions and move randomly in different directions. In an external electric field, they drift against the direction of the field. The positive ions are made up of the nuclei and the bound electrons remain held in their fixed positions.

Why are cars safer during lightning?

Options:

Because it is made up of metal

Car is insulated

Electric field inside a conductor is zero

None of the above

Correct Answer:

Electric field inside a conductor is zero

Explanation:

Cars are safe from lightning because of the metal cage surrounding the people inside the vehicle. This may sound counter-intuitive because metal is a good conductor of electricity, but inside the conductor electric field is zero.